5 1080ti Mining Rig Freezing. Power related questions

[DigitalLemming]

Having some issues I need resolved.

I'm having stability Issues. My miner freezes anywhere between 5 minutes to 3 hours. I'm certain it's the power since It's way overbuilt for a miner. I have no problems with the GPU detection. I'm using awesome miner at the moment mining lyrarev2. I also was freezing using a VTC miner. I will be switching to nicehash again when that's back online. I'm running on PCI "Gen 1", but have tried "Gen 2", "Gen3" and "auto" and it still freezes.


Build is as follows
 
Windows 10 PRO
MSI z270 Pro Gaming Carbon
Intel I3 7100
Ballistix Sport LT 16GB Kit (8GBx2) DDR4 2666 MT/s
2x Rosewill CAPSTONE1000W Connected BY Add2PSU(authentic)
5X Nvidia 1080ti mixed brands
128gb M.2 SSD
6-Pack Mining Dedicated Riser USB 3.0 PCI-e Express 1X to 16X Riser Card Extender

I have 2x 1000w gold rated PSU's connected by an add2psu. The main PSU powers all 5 risers, the motherboard and 2 GPU's. The other PSU powers the other 3 GPU's. I have the GPU's undervolted to 70%.

Tests- When I run 4 GPU's appears to be stable. I've also tried running 4x 1080ti's on the slave PSU and just 1x 1080ti and the mobo on the other. It appears to be stable however I'm afraid to run 4x 1080ti's on only 1000W even if they are undervolted to 70%.

Questions

1 I can't get clear answer's on the 1080ti wattage. I read 250 watt each, but on load may be more. How much power should they consume if they are undervolted to 70%. Is this safe to run 4x of them on 1x 1000w PSU?

2 How much power do the risers deliver to the GPU's? The light's and fans continue to run even if the power from the slave PSU is not connected.

3 Lastly I'm confused on the "core clock" and "memory clock" on MSI Afterburner. Would adjusting these down help? What setting are ideal?

I also know I'm going to get suggest to buy a 1600W Server power supply. I felt 2x 1000w units should have been enough for this built. Any way I can wire this baby up with my current setup without having to buy more? Worst case I can add another 650 watt gold rated PSU I have on hand but it won't fit in my rig pretty and 3 chained together PSU's sounds sketchy.

Thanks for the help I look forward to the advice I receive.

[popc0r3]

1 I can't get clear answer's on the 1080ti wattage. I read 250 watt each, but on load may be more. How much power should they consume if they are undervolted to 70%. Is this safe to run 4x of them on 1x 1000w PSU?

250W is during maximum load so if you run them at 70% we should roughly expect 175W per card. You could get a Wattmeter and keep it in your socket if you want the "true numbers". My say is that is safe to run 4 cards but going higher than 4 you might wanna be careful. Alternatively you could try powering the risers from slave PSU and run 3 gpus on slave and 2 on main.

2 How much power do the risers deliver to the GPU's? The light's and fans continue to run even if the power from the slave PSU is not connected.

I cant answer how much but i definitely think your main PSU. Im curious as to how you are powering the risers, are you using a single cable with multiple sata connectors to power them?

Heres some useful information: https://forum.ethereum.org/discussion/9495/the-correct-way-of-powering-the-risers-for-the-470-480

3 Lastly I'm confused on the "core clock" and "memory clock" on MSI Afterburner. Would adjusting these down help? What setting are ideal?

Clock frequency has little to no impact on power consumption, what matters is the voltage. What settings are ideal are different for each card and since you have mixed brands you basically have to do some trial and error on each card. Core clock seems to have the most impact on mining Lyra2rev2.

Hers a list for comparison where you can see what other 1080 ti's are getting and their settings: http://www.verters.com/vertcoin-hardware-list

Best of luck!

[shubaduba]

1. To know exact power draw, launch "C:\"Program Files"\"NVIDIA Corporation"\NVSMI\nvidia-smi.exe -l"

2. Risers deliver up to 30w.

3. In general, 1080ti do not like overclocking much, so I set +60-100 core and +150-300 mem.
But if you use non-memory dependent algos (not neoscrypt, ethash or equihash), you better set mem to -500. That will lower total power consumed, reduce GPU temps and reduce mem timings, so it will be even more responsible and efficient for algos like lyra2v2.

I follow the rule when each GPU must be powered by only one PSU - both riser and GPU itself.
If you use motherboard PCIex port directly, then do not mix it with risers on the same PSU.

So, you can install 2 GPUs in your motherboard and connect it to the main PSU, and other 3 GPUs - via risers, completely powered by slave PSU.

[DigitalLemming]

Okay, my current setup everything is on risers unless I un assemble the whole frame to adjust it to add GPU's straight to the motherboard.

The risers are powered by 2 different sata chain cables coming from the main PSU. The thought of running all Risers and 3 GPU's from the Slave PSU and the other GPU's and the mobo from the main PSU is interesting.

I thought I read somewhere that since the risers are extensions of the motherboard it may be safer to run them from the same PSU that powers the motherboard. I've also read not to cross the power like shubaduba suggested. This is why I'm at a loss.

I did fry a mother board before. I had 2 Risers and 2 GPUs on the first PSU and 3 risers and 3 GPU's on the second PSU. The system was not shutting down properly, the second PSU would not shut down and would somehow kick the first PSU back on and start everything up. I had the system shut off and plugged a Riser into the mother board and the power discharging started the whole rig up and fried the mobo so I'm paranoid.

[shubaduba]

I thought I read somewhere that since the risers are extensions of the motherboard it may be safer to run them from the same PSU that powers the motherboard. I've also read not to cross the power like shubaduba suggested. This is why I'm at a loss.

Risers do not transfer any power through USB cable from motherboard. All pins are used for data transfer. So "risers are extensions of the motherboard" only partially, not in case of power delivery.

I did fry a mother board before. I had 2 Risers and 2 GPUs on the first PSU and 3 risers and 3 GPU's on the second PSU. The system was not shutting down properly, the second PSU would not shut down and would somehow kick the first PSU back on and start everything up. I had the system shut off and plugged a Riser into the mother board and the power discharging started the whole rig up and fried the mobo so I'm paranoid.

Can you show which type of PSU-to-PSU synchronizer is installed?
You can try to swap PSUs. Some of them do not like being slave.
Risers do not respond for proper PSU power up/down.
I have never encountered such problems with any of 8 rigs I have built.

It is not recommended to connect directly into motherboard PCIex port, because GPUs will draw much power from MB.
I thought you have no enough risers.
But if you have, then 3 + 2 as you described would be perfect power balanced scheme.

To avoid ground/static burnouts it is highly advised to connect both PSUs cases with any 18+ AWS cable

[usd.dev]

Recently I bought myself such a video card, at the moment Kalkulus's mine, when using CudaMiner shows a very good result, I advise you to try, in the melting time the complexity is very low and the cost will allow you to buy coins for the next year.

[popc0r3]

The risers are powered by 2 different sata chain cables coming from the main PSU. The thought of running all Risers and 3 GPU's from the Slave PSU and the other GPU's and the mobo from the main PSU is interesting.

I see many people recommending not using SATA to power the risers at all and that running multiple is a potential fire hazard. See: https://www.reddit.com/r/gpumining/comments/6pqb8i/question_about_safe_power_draw_for_pcie_risers/

If your running 5 risers on 2 chains that might be an issue since SATA cant provide enough power per chain. If you can run the risers directly on molex from psu i think that would be preferable.

I thought I read somewhere that since the risers are extensions of the motherboard it may be safer to run them from the same PSU that powers the motherboard. I've also read not to cross the power like shubaduba suggested.

Yes that is probably wise to avoid having different electrical sources per component. I think shubaduba's suggestion running two cards directly on the motherboard might be a solid idea. Have 3x gpu and 3x risers completely powered by slave.

Thats all ive got, good luck!

[shubaduba]

I see many people recommending not using SATA to power the risers at all and that running multiple is a potential fire hazard. See: https://www.reddit.com/r/gpumining/comments/6pqb8i/question_about_safe_power_draw_for_pcie_risers/

If your running 5 risers on 2 chains that might be an issue since SATA cant provide enough power per chain. If you can run the risers directly on molex from psu i think that would be preferable.

Yeah, I try not to use SATA risers. 6 pins are the best, then MOLEX 4-pin in my list.

[DigitalLemming]

Alright guys I believe I have all the info I need. Thanks a ton for taking the time to respond. I’ll do some experiments over the next few days and will report back hopefully with success.

Worst case I’ll switch out the sata risers and upgrade the total power and it should work

[Khayn93]

I'm having problems with a 6x GPU mining rig (6xZotac 1080 ti extreme & 2x 1000W psu Corsair HX1000i)

GPU powered like this:
GPU --> Dual 8 pin --> VGA (8PIN) in PSU (1 cable pr PSU). - Hence; 1 Y cable pr. GPU. 1x8pin in PSU, and 2x 8pins in GPU.

Riser powered:
Riser --> 6 pin --> SATA-6PIN cable-chain (from Corsair) --> PSU. (1 riser pr. sata-chain)

First question:
Will 1 8pin to dual 8pin to GPU be enough if you want to OC it? (1x 8pin cable only provides 150W right, or it provides more when its dual 8pin?)
Or should I use 2 separate 8 pins to power 1 GPU.

Second question:
Should I power Rises in another way? I read about fire hazards etc.
Should I power risers like this?

PSU --> VGA (8pin) --> 2x (6+2 pins) powering to risers.

(If I should use two separate 8pins pr. GPU, then I would need 6x VGA(8pins) slots in my PSU.)
(That's fine, because I have 6 slots in 1 PSU, and 8 in another (where MOBO goes in).
(However, if I should also power risers through VGA(8pins slots), then I don't have enough slots...)

Help needed - willing to pay!

[Khayn93]

Or can I power like this?

2 pcs 8pin to dual 8pin pr GPU.
1x 8 pin in PSU, and 1x 8pin in GPU (leaving 1 (6+2)pin un-used)
1x 8 pin in PSU, and 1x 8pin in GPU + the other 6 pin in riser).

This would make me possible to power 3x risers, and 3 1080ti from 6 outlets in PSU. (2 outlets pr. GPU)
(And no SATA or MOLEX problems powering the risers)


https://imgur.com/o0XIRDf

[fanatic26]

Or can I power like this?

2 pcs 8pin to dual 8pin pr GPU.
1x 8 pin in PSU, and 1x 8pin in GPU (leaving 1 (6+2)pin un-used)
1x 8 pin in PSU, and 1x 8pin in GPU + the other 6 pin in riser).

This would make me possible to power 3x risers, and 3 1080ti from 6 outlets in PSU. (2 outlets pr. GPU)
(And no SATA or MOLEX problems powering the risers)


https://imgur.com/o0XIRDf

You already have a thread of your own about this. Coming in and hijacking someone elses thread is not kosher.